With a new bokashi bin ready and a spring-like day, there has been no better opportunity to enjoy some time in the garden. Another of those long-awaited days arrived this morning, when I could put my back into the next phase of the garden makeover.

The project in question was a hugelbed to use up all the wood I have accumulated from excavating previous beds as well as other branches I’ve collected. I’m going to be scaling back annual vegetable growing as the forest garden develops but I don’t want to give it up entirely. I’m too fond of my own broad beans and tomatoes.

The spot I’d chosen for the hugelbed is undoubtedly the sunniest, getting some winter sun in spite of the high fence and tall trees on the east side of the garden. From past experience, whatever I grow here does tend to do well.

First of all, the bluebells needed to go. Then it was some feat to get the soil moved, there already being wood from making a hugelbed in this position previously. Over time, the soil settles into the nooks and crannies.

I could of course have left the wood that was already there and piled the rest on top. However, I want the soil on top of the mound to be as deep as possible. In the short term, I need to conceal the whiff of bokashi and, in the longer term, I need the soil to be deep enough to grow things.

What I’ve found over the last four years of growing on such mounds is that, once the soil settles, there isn’t enough for plant roots and they soon hit solid wood. You might wonder why I’m going to the trouble of putting the wood in the soil then. Thus, the reasons are:

As the wood rots, it should soak up water which the plants can then use. With my soil being sandy loam, should the wood eventually rot and indeed become a sponge, hopefully therefore the hugel beds will be less drought-prone.

Also as the wood rots, it should turn to long-lasting compost and increase the depth of top soil. With mine being so thin, to have even a few centimetres’ extra depth would be excellent.

Even though I have yet to experience these advantages, I am hopeful that the theory will come true in practice, once the rot starts. Since beginning the experiment in 2015, I have learned that it is better if the wood has already started to decompose before it goes in the ground. That is logical but supplies of such, for me, are hard to come by.

As my soil is also naturally dry, the decomposition process is going to take longer than it would in a wetter climate with a different soil profile. In fact, I dare say the environment in my back garden would be an archaeologist’s dream if there were any historical artefacts to be found. But perhaps they’ll never need to puzzle over all the branches they discover a thousand years from now if climate change wipes us all out.

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About Helen

I have always been interesting in living a more environmentally friendly lifestyle and used to do what I could. Now, I have come to realise that we have reached such a point in terms of environmental degradation that it is more important - perhaps - to focus on building resilience. I therefore do as much as I can to reuse, grow my own and encourage a supportive community, for example. I also keep reading and learning all the time.

12 Responses to The last hugelbed

I started with almost no topsoil over compacted stone. After 20 odd years even the paths and banks which have had to do it all without help have some soil and things are growing – some of them unwelcome weeds but at least the place has turned from looking like a badly run quarry to green. Someone told me that for every 8cm deep layer of newly built compost heap I would get 1cm of finished compost so to get 40cm of soil in my raised beds has involved piling over 3m of material on them bit by bit. Your wood will rot down eventually and if you keep at it you will build a reasonable depth of soil – just not by next week or even next year. It will be good rich soil, you will know there are no toxic materials in it and whilst it will have cost you time and effort it will not have cost money. I haven’t tried it on hugelbeds but piling layers of cardboard over unrotted material before putting soil on helps slow down the process of the soil dropping or washing down into the spaces. I get as much as I want from a local agricultural supplier. They are a bit bewildered by me but it saves them paying to get rid of it. You might find a local shop or supermarket happy to let you take their old boxes away. It does rot down but then still helps to fill up the gaps and it is extra compost. The plain brown stuff is better than the glossy printed but sometimes beggars can’t be choosers. Good luck.

I have put cardboard into the hugelbed, as I did with the others. The contents of the bokashi went over the wood before the cardboard, though, as I wanted to smother the smell as much as possible. However, I would imagine the soil is needed round the wood to help it decompose.

Anyway, one thing I keep forgetting to mention is the number of worms I’ve been finding wherever I’ve added bokashi to the soil. I feel sorry for them with all the digging I’ve been doing. Thankfully, that is more or less it now, I hope!

I’m following your hugel experiments with great interest! I think it would work well here in the dry zone. I’ve started a huge hugel hole & heap at Dreamland, with the hope of it housing a big tree, but I need to take it further. Reading your blog, it sounds that the more I allow the wood to decompose before putting on soil, the better – may after next winter’s rains… Great reading, thanks.

When you say ‘housing a big tree’, you mean chopping up a dead one rather than growing a tree on top of the mound?

Anyway, it seems it would be worthwhile letting your wood rot a bit first. Not sure one year is enough, but I guess it depends on climate. Some of the branches I put in yesterday’s bed had already been in the ground 18 months after 18 months of waiting, chopped on the ground. They are still as hard as when they were pollarded.

I’ve put all my older wood back in the ground, along with newer stuff I’ve collected, even if it hasn’t ‘matured’, simply because the job needs doing and I don’t know if the wood will ever rot in my dry climate with such sandy soil.

Hi Helen – I mean growing a big tree on the mound! There are a bunch of big branches in there now for more than a year already – they were too thick to mulch when we cleared the area. But there’s still a lot of air around the branches. I think I must start filling it with dry leaves, clippings etc…
Sure that makes sense putting your wood back in the ground – that’s, in my mind anyway, the best place for them to rot.
Cheers

Martin, I understand that growing a tree in such a mound will be bad for it. You see, the mound will subside – and before even the first year is out, going on my experience. Better to plant the tree beside the mound, so its roots can dig into the goodness but the trunk won’t fall over. I wouldn’t want you to lose your tree!

OK that makes sense (I’ve never studied Hugel culture). So I can rather arrange the mound as a circle wide around the tree and grow shorter term companions in there; and then as the mound turns into long term compost, the tree roots will get the benefit? That way the tree is on stable ground for the wind too… 🙂